Using Exchange dynamic links to get next events / unread mails

When setting Exchange Authentication method as "Save password in user preferences", the popup to set password is not displayed anymore for user who do not set it already.

Version of plugins :

exchange : 1.15.0M5
messaging-connector : 1.11.0
link-directory : 2.18.0M8   --> it seems that it worked correctly in 2.18.0M5